1. Field of the Invention
This invention relates, in general, to hardware for appliances, and in particular, to a device which combines the functions of a plug-in, hinge pin for an appliance door and means for bringing electrical power into the door, for use on refrigerators and the like.
2. Summary of the Prior Art
Commerical refrigerators and refrigerated display cases are employed in markets, food-vending operations, liquor stores and the like for the simultaneous preservation of freshness and attractive display of foodstuffs to the customer. Typically, commercial display cases have large, swinging doors which incorporate large areas of multiple-layered glazing to permit the customer to see, select and access the refrigerated product easily, while preventing a heat loss into the refrigerated space.
Unfortunately, humidity conditions can develop within and/or without the unit which cause condensation to form on the glazed portions of the door, which inhibits a clear view of the product by the customer. This problem has been overcome by the installation of small-wattage heaters within the door, sometimes on the glasing itself, which are thermostatically activated to evaporate or prevent the moisture, resulting in enhanced visibility through the door.
As a consequence of the need for electrical heaters, it becomes necessary to bring electrical power into the door itself, which is typically hinged at the top and bottom corners of one vertical edge of the door by means of a fixed hinge pin passing into a bearing opening withint the frame of the door. Typically, this connection of the door with electrical power is accomplished by means of a "service loop", i.e., a loop of two or more conductors exiting a point on the frame of the appliance and connecting by means of a male/female connector combination either at some point on the surface of, or within, the swinging door. Aside from the cosmetic, or appearance, problem that this may present, the service loop is required to undergo a flexion each time the door is opened and closed by the customer, leading to wear and tear on the conductors over a period of time. An additional problem presented by this method is that of having the conductors exposed to the external surface of the door and appliance, which renders them subject to abrasion and impact by passing objects.
Although efforts have been made to overcome some of the foregoing problems by encapsulating the service loop conductors within flexible conduits which serve to protect and dress up the external aspect of the conductors, it would be more desirable if the electrical connection could be contained entirely within the frame or mounting structure of the refrigerator and the door itself.
Another, related problem with hinged appliance doors is that of their quick removal and replacement for maintenance and repair. Conventionally, the hinge pins for the door are carried on brackets which are installed and removed by the use of threaded fasteners and conventional hand tools. Also typically, this hardware is not designed to be reversible, i.e., usable on appliances which are adapted to have either "right-hand opening" or "left-hand opening" doors. Thus, it would be desirable to have a hinge pin which could be simply and quickly plugged or snapped into a mating receptacle in the appliance, which is adapted for either right-hand or left-hand applications, and which incorporates integrally the function of an electrical connection for the door, thereby eliminating any need for a separate, external service loop.